Synthetic Aperture Digital Beamsteering Array for Global Positioning System Interference Mitigation: A Study on Array Topology

The Global Positioning System (GPS) satellite navigation system is deeply intertwined with civilian everyday life. Unfortunately for the civilians that use the system, the GPS system is vulnerable to external interference. Antenna arrays with Direction of Arrival (DoA) signal identification and beamsteering provide a very effective technique for mitigating directional interference by moving the antenna gain toward the Signal of Interest (SOI) or away from the Signal not of Interest (SNOI), however, such systems are typically too large to integrate or require more processing capabilities than civilian devices are able to provide. Synthetic aperture arrays are a means to reduce the array size but provide a similar interference protection with a smaller processing capability overhead. This thesis assists in array selection by providing simulated gains of different switched antenna arrays. The Uniform Circular Array (UCA), rectangular array, random array, random full aperture, random sequential, ring (UCA random hybrid) topologies are evaluated. In a pure synthetic beamsteering system in the presence of continuous wave (CW) interference, it is determined that array topology has marginal impact on Signal to Interference Noise Ratio (SINR) as each array's results show very similar performance. With the two CW scenarios in the absence of null steering, the UCA maintains the highest performance using the smallest number of antenna elements.